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Balance Sheet Components - Summary of Asset Retirement Obligation Liability (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]      
Asset retirement obligations, beginning balance $ 64,858 $ 59,548 $ 63,150
Additions 17,337 5,774 8,713
Adjustments (4,676) (871) (14,874)
Accretion expense 3,349 2,438 2,932
Impact of foreign currency exchange (2,386) (2,031) (373)
Asset retirement obligations, ending balance $ 78,482 $ 64,858 $ 59,548